Novon 2: 270. 1992.
Herbs, annual, 1–9 dm, monoecious. Stems usually single from base, much branched from near middle, densely stellate-lepidote appearing silvery. Leaves not clustered; stipules rudimentary; petiole 0.1–0.5 cm, glands absent at apex; blade lanceolate-linear to ovate-lanceolate, 1.5–4 × 0.1–0.4(–1.5) cm, base acute to cuneate, margins entire, apex acute, abaxial surface silvery, stellate-lepidote, adaxial surface green, sparsely stellate-hairy, hairs with few radii. Inflorescences bisexual, spikes, 0.3–3 cm, staminate flowers 1–12, pistillate flowers 1–6. Pedicels: pistillate absent, staminate 0–1 mm. Staminate flowers: sepals 5, 1 mm, abaxial surface lepidote; petals 5, spatulate, 0.6–1 mm, abaxial surface glabrous except margins villous; stamens 5–7. Pistillate flowers: sepals (4–)5, equal, 1–1.5 mm, margins entire, apex straight, abaxial surface lepidote; petals 0; ovary 1-locular; styles 3, 0.5–0.8 mm, minutely 2-fid, terminal segments 3 or 6. Achenes 2.5–3 × 1–1.2 mm, smooth; columella absent. Seeds 2–2.5 × 1 mm, surface not visible because seed coat adherent to fruit wall.
Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Miss., Mo., N.C., N.J., Okla., Pa., S.C., Tenn., Tex., Va.
Varieties 2 (2 in the flora).
|1||Inflorescences 1–3 cm; achenes usually 3–6, densely stellate-lepidote, hairs ± spreading, radii separate most of length, umbos usually sharp, sometimes rounded; leaf blade adaxial surface hairs not overlapping.||Croton michauxii var. michauxii|
|1||Inflorescences usually less than 1 cm; achenes 1–2, sparsely stellate-lepidote, hairs appressed, radii joined most or all of length, umbos usually blunt, rarely sharp; leaf blade adaxial surface hairs overlapping near midvein.||Croton michauxii var. elliptica|